Radar systems are used to detect objects, and to determine distances, directions, and/or velocities. In motor vehicles, radar systems are used, for example, for spacing, collision warning, and in automatic speed control systems. A basic characteristic common to all of these applications is that the radar system, or more precisely its directional antenna, must be precisely adjusted to a desired principal beam direction. In the case of the a motor vehicle application, the principal beam direction is often selected to be, for example, parallel to the travel axis of the vehicle. Because of installation and manufacturing tolerances or, for example, after an accident, adjustment must specifically be possible even when the radar system is installed in a mount provided on the motor vehicle.
One possibility for achieving this object is to provide a mount for the radar system, or at least its directional antenna, which is modeled on a motor vehicle headlight suspension or mounting system. In this solution, the radar system or its directional antenna is attached at three points lying in a plane perpendicular to the principal beam direction, preferably in an L-shaped configuration with respect to one another. The two outer suspension points are thus offset in two directions with respect to one another. The two outer points each consist of a threaded rod equipped at one end with a ball head, the ball head allowing the threaded rod to move in a mount. The third, center, suspension point is also movably mounted by means of a ball head. However, this third suspension point generally does not have displacement capability in the form of a threaded rod or the like. Thus, when the radar system or its directional antenna is moved at one of the two-outer threaded rods, its principal beam direction tilts about an axis that is formed by the respective other two suspension points. The principal beam direction of the radar system can thus be adjusted, at two displacement screws or two threaded rods, in two directions (preferably horizontally and vertically) located perpendicular to one another.
It is characteristic of this solution that the adjustment apparatus be combined with the mechanical suspension of the radar system or its directional antenna. Accordingly, the adjustment apparatus must in each case be re-adapted to different installation environments, particularly in the case of a physically small radar system housed in its entirety in a housing, as is used predominantly in a motor vehicle. These different installation environments result, for example, if one and the same radar system is to be installed in different motor vehicle models. In some circumstances, not only the mechanical suspension system, but also the adjustment mechanism must be redesigned in each case. This means a considerable outlay for adapting an existing radar system to other vehicle models. Moreover an external adjustment apparatus of this kind, i.e., one located outside the compact housing, requires additional space for installation in a motor vehicle.